CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority of Japanese patent applications 2000-266393, filed Sep. 4, 2000, 2000-348032, filed Nov. 15, 2000, and 2000-363130, filed Nov. 29, 2000.
1. Field of the Invention
The present invention relates to a periphery monitoring system, more particularly relates to a periphery monitoring system able to monitor the periphery of a vehicle, predict cut-in of another vehicle from the side, and determining a range by which the mounted vehicle may advance.
2. Description of the Related Art
One cruise control system of a vehicle is the auto cruise control (ACC) system. The ACC system controls the speed of a mounted vehicle based on the relative speed of the mounted vehicle with respect to a vehicle in front and an inter-vehicle distance between the mounted vehicle and the vehicle in front, that is, the relative distance.
That is, the ACC system is comprised of a vehicle controller for controlling an opening degree of a throttle valve and a gear ratio of a transmission and a detector for detecting the relative speed and relative distance.
To ensure safe cruising of the vehicle, however, it is important to monitor not only the vehicle in front, but also vehicles cruising at the sides of the mounted vehicle and decide on the existence of vehicles cutting in front from the sides and the range which the mounted vehicle can safely cruise based on the results of the monitoring.
Radar has been used for detecting the relative speed and relative distance of a mounted vehicle with respect to a vehicle in front in the past, but it has not been possible to accurately obtain a grasp of the conditions at the periphery of a mounted vehicle.
On the other hand, television cameras and other image sensors are suitable for obtaining a grasp of the conditions at the periphery of a mounted vehicle, but are not suitable for obtaining a grasp of the relative speed and relative distance of a mounted vehicle with respect to another vehicle.
An object of the present invention is to provide a periphery monitoring system combining radar and an image sensor and able to obtain an accurate grasp of the existence of a target at the periphery of a mounted vehicle and to determine the existence of a cut-in vehicle and a range to which a mounted vehicle may safely advance.
According to a first aspect of the invention, there is provided a periphery monitoring system provided with a target detecting means for detecting a target, a first judging means for judging which of a first region along a path of advance of a mounted vehicle, a second region comprised of a region near the outside of said first region, and a third region other than said first and second regions a target detected by said target detecting means is present in, and a first output means for outputting target detection information output from said target detecting means to a cruise control means for controlling the cruising of said vehicle based on the result of judgement of said first judging means.
According to the periphery monitoring system according to the first aspect of the invention, it becomes possible to judge which of the plurality of regions centered about the vehicle a target detected by the target detecting means is in.
According to a second aspect of the invention, there is provided a periphery monitoring system provided with a target detecting means for detecting the presence of a target in front, a distance to the target, and a relative speed of movement of the target and a cut-in predicting means for predicting a cut-in of a target into a cruising lane of the mounted vehicle based on an output of said target detecting means.
According to the periphery monitoring system according to the second aspect of the invention, it becomes possible to judge if a target detected by said target detecting means is liable to cut into a cruising lane of the vehicle.
According to a third aspect of the invention, there is provided a periphery monitoring system provided with a target detecting means for detecting the existence of a target in front, a distance to the target, and a relative speed of the target and an advance range determining means for determining a range to which a mounted vehicle may advance based on output of said target detecting means.
According to the periphery monitoring system according to the third aspect of the invention, it becomes possible to determine the advance range of the mounted vehicle based on information relating to a target detected by said target detecting means.